Two major back-to-back earthquakes struck Venezuela on Wednesday evening. More than 160 people have been confirmed dead on Thursday morning with hundreds more injured, and the death toll is expected to rise.

CNN is tracking developments, in maps and charts.

The larger 7.5 magnitude earthquake struck only 40 seconds after a 7.2 magnitude foreshock. This marks the largest recorded earthquake in Venezuela for more than a century.

Earthquakes are measured by magnitude on a logarithmic scale — so each whole number increase translates to 32 times more energy released by the quake. Due to how the scale works, the second 7.5 magnitude quake was actually twice as large as the first, which had a magnitude of 7.2.

Both are classified as “major” earthquakes, and were felt both in Venezuela and in neighboring Colombia. Serious damage to buildings and infrastructure is expected to be reported in the coming days.

Internet connectivity dropped sharply across the Venezuela as the quakes damaged power and telecommunications infrastructure, according to data from watchdog Netblocks.